CBTX : Investor Presentation Q4 2021

NASDAQ: CBTX

CBTX, Inc.

Fourth Quarter 2021 Investor Presentation

SAFE HARBOR STATEMENT AND NON-GAAP FINANCIAL MEASURES

NON-GAAP FINANCIAL MEASURES

This presentation contains certain non-GAAP (generally accepted accounting principles) financial measures, including tangible equity, tangible assets, tangible book value per share, tangible equity to tangible assets, return on average tangible equity, and pre-provision net revenue. The non-GAAP financial measures that CBTX, Inc. (the "Company") discusses in this presentation should not be considered in isolation or as a substitute for the most directly comparable or other financial measures calculated in accordance with GAAP. A reconciliation of the non-GAAP financial measures used in this presentation to the most directly comparable GAAP measures is provided at the end of this presentation.

FORWARD-LOOKING STATEMENTS

This presentation may contain certain forward-looking statements within the meaning of the securities laws that are based on various facts and derived utilizing important assumptions, current expectations, estimates and projections about the Company and its subsidiary. Forward-looking statements include information regarding the Company's future financial performance, business and growth strategy, projected plans and objectives, as well as projections of macroeconomic and industry trends, which are inherently unreliable due to the multiple factors that impact economic trends, and any such variations may be material. Statements preceded by, followed by or that otherwise include the words "believes," "expects," "anticipates," "intends," "projects," "estimates," "plans" and similar expressions or future or conditional verbs such as "will," "should," "would," "may" and "could" are generally forward-looking in nature and not historical facts, although not all forward-looking statements include the foregoing. Further, certain factors that could affect our future results and cause actual results to differ materially from those expressed in the forward-looking statements include, but are not limited to: natural disasters and adverse weather on the Company's market area, acts of terrorism, pandemics, an outbreak of hostilities or other international or domestic calamities and other matters beyond the Company's control; the Company's ability to manage the economic risks related to the impact of the COVID-19 pandemic (including risks related to its customers' credit quality, deferrals and modifications to loans); the geographic concentration of the Company's markets in Houston and Beaumont, Texas; the Company's ability to manage changes and the continued health or availability of management personnel; the amount of nonperforming and classified assets that the Company holds and the time and effort necessary to resolve nonperforming assets; deterioration of asset quality; interest rate risk associated with the Company's business; national business and economic conditions in general, in the financial services industry and within the Company's primary markets; sustained instability of the oil and gas industry in general and within Texas; the composition of the Company's loan portfolio, including the identity of the Company's borrowers and the concentration of loans in specialized industries; changes in the value of collateral securing the Company's loans; the Company's ability to maintain important deposit customer relationships and its reputation; the Company's ability to maintain effective internal control over financial reporting; the Company's ability to pursue available remedies in the event of a loan default for loans under the Paycheck Protection Program, or PPP, and the risk of holding such loans at unfavorable interest rates and on terms that are less favorable than those with customers to whom the Company would have otherwise lent; volatility and direction of market interest rates; liquidity risks associated with the Company's business; systems failures, interruptions or breaches involving the Company's information technology and telecommunications systems or third- or fourth-party servicers; the failure of certain third- or fourth-party vendors to perform; the institution and outcome of litigation and other legal proceedings against the Company or to which it may become subject; the operational risks associated with the Company's business; the costs, effects and results of regulatory examinations, investigations, or reviews or the ability to obtain required regulatory approvals; changes in the laws, rules, regulations, interpretations or policies relating to financial institution, accounting, tax, trade, monetary and fiscal matters; governmental or regulatory responses to the COVID-19 pandemic that may impact the Company's loan portfolio and forbearance practice; further government intervention in the U.S. financial system that may impact how the Company achieves its performance goals; the risk that the cost savings and any revenue synergies from the merger may not be fully realized or may take longer than anticipated to be realized; disruption to the parties' businesses as a result of the announcement and pendency of the merger; the occurrence of any event, change or other circumstances that could give rise to the termination of the merger agreement; the risk that the integration of each party's operations will be materially delayed or will be more costly or difficult than expected or that the parties are otherwise unable to successfully integrate each party's businesses into the other's businesses; the failure to obtain the necessary approvals by the shareholders of Allegiance or the Company; the amount of the costs, fees, expenses and charges related to the merger; the ability by each of Allegiance and the Company to obtain required governmental approvals of the merger (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the transaction); reputational risk and the reaction of each company's customers, suppliers, employees or other business partners to the merger; the failure of the closing conditions in the merger agreement to be satisfied, or any unexpected delay in closing the merger; the possibility that the merger may be more expensive to complete than anticipated, including as a result of unexpected factors or events; the dilution caused by the Company's issuance of additional shares of its common stock in the merger; general competitive, economic, political and market conditions; and other factors that may affect future results of the Company and Allegiance including changes in asset quality and credit risk; the inability to sustain revenue and earnings growth; changes in interest rates and capital markets; inflation; customer borrowing, repayment, investment and deposit practices; the impact, extent and timing of technological changes; capital management activities; and other actions of the Board of Governors of the Federal Reserve System, Federal Deposit Insurance Corporation and OCC and legislative and regulatory actions and reforms; and other risks, uncertainties, and factors that are discussed from time to time in the Company's reports and documents filed with the SEC. Additionally, many of these risks and uncertainties have been elevated by and may continue to be elevated by the COVID-19 pandemic.

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SAFE HARBOR STATEMENT AND NON-GAAP FINANCIAL MEASURES

The foregoing factors should not be construed as exhaustive and should be read together with the other cautionary statements included in the Company's Annual Report on Form 10-K, filed with the Securities and Exchange Commission, or SEC, and other reports and statements that the Company has filed with the SEC. If one or more events related to these or other risks or uncertainties materialize, or if the Company's underlying assumptions prove to be incorrect, actual results may differ materially from what it anticipates. Accordingly, you should not place undue reliance on any such forward- looking statements. Any forward-looking statement speaks only as of the date on which it is made, and the Company does not undertake any obligation to publicly update or review any forward- looking statement, whether as a result of new information, future developments or otherwise. New factors emerge from time to time, and it is not possible for the Company to predict which will arise. In addition, the Company cannot assess the impact of each factor on its business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Copies of the SEC filings for the Company are available for download free of charge from www.communitybankoftx.com under the Investor Relations tab.

Allegiance and the Company disclaim any obligation and do not intend to update or revise any forward-looking statements contained in this communication, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by federal securities laws. As forward-looking statements involve significant risks and uncertainties, caution should be exercised against placing undue reliance on such statements.

Information about the Merger and Where to Find It

This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval.

In connection with the proposed merger, the Company intends to file a registration statement on Form S-4 with the SEC to register the shares of the Company's common stock that will be issued to Allegiance shareholders in connection with the merger. The registration statement will include a joint proxy statement/prospectus and other relevant materials in connection with the proposed merger, which will be sent to the shareholders of the Company and Allegiance seeking their approval of the proposed merger.

WE URGE INVESTORS AND SECURITY HOLDERS TO READ THE REGISTRATION STATEMENT ON FORM S-4, THE JOINT PROXY STATEMENT/PROSPECTUS INCLUDED WITHIN THE REGISTRATION STATEMENT ON FORM S-4 AND ANY OTHER RELEVANT DOCUMENTS FILED OR TO BE FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IN CONNECTION WITH THE PROPOSED MERGER BECAUSE THEY CONTAIN IMPORTANT INFORMATION ABOUT ALLEGIANCE, THE COMPANY AND THE PROPOSED MERGER.

Investors and security holders may obtain free copies of these documents, once they are filed, and other documents filed with the SEC by Allegiance or the Company through the website maintained by the SEC at https://www.sec.gov. Documents filed with the SEC by the Company will be available free of charge by accessing the Company's website at www.communitybankoftx.com under the heading "Investor Relations" or, alternatively, by directing a request by mail or telephone to CBTX, Inc., 9 Greenway Plaza, Suite 110, Houston, Texas 77046, Attn: Investor Relations, [phone], and documents filed with the SEC by Allegiance will be available free of charge by accessing Allegiance's website at www.allegiancebank.com under the heading "Investor Relations" or, alternatively, by directing a request by mail or telephone to Allegiance Bancshares, Inc., 8847 West Sam Houston Parkway, N., Suite 200, Houston, Texas 77040, [phone].

Participants in the Solicitation

The Company, Allegiance and certain of their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the shareholders of the Company and Allegiance in connection with the proposed merger. Certain information regarding the interests of these participants and a description of their direct or indirect interests, by security holdings or otherwise, will be included in the joint proxy statement/prospectus regarding the proposed merger when it becomes available. Additional information about the directors and executive officers of the Company and their ownership of the Company's common stock is set forth in the Company's proxy statement for its annual meeting of shareholders, filed with the SEC on April 14, 2021. Additional information about the directors and executive officers of Allegiance and their ownership of Allegiance's common stock is set forth in Allegiance's proxy statement for its annual meeting of shareholders, filed with the SEC on March 10, 2021. These documents can be obtained free of charge from the sources described above.

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COMPANY SNAPSHOT

• Founded in 2007 and completed IPO in November 2017
• On 11/5/2021, entered into a definitive merger agreement with Allegiance Bancshares, Inc.
• Resolved outstanding regulatory matters associated with BSA/AML program in December 2021
• Primarily a business bank with 34 banking centers located across Houston, East Texas and Dallas
• Strong credit culture and experienced management team with deep ties in the markets served
• Low-costcore funding - total deposits of $3.8 billion as of 12/31/2021
• Strong insider ownership of 26% as of 12/31/2021
• Strong capital levels with total risk-based capital ratio of 16.42%, tier 1 risk-based and common equity tier 1 capital ratios of 15.31% of 12/31/2021

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ANNOUNCED MERGER WITH ABTX, INC.

• Creates a premier Texas financial institution by combining two of the largest Houston- focused banks
• Generates significant shareholder
  value through materially enhanced metrics
• True merger-of-equals - combined management team and equal board contribution
• Complementary branch network, with meaningful overlap to support cost savings
• Shared vision, community focus, and commitment to clients and employees

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